"Free speech not only lives, it rocks," a beaming Oprah Winfrey said Thursday after jurors rejected a multimillion-dollar defamation lawsuit by Texas cattlemen. The Amarillo, Texas, jury decided the television talk show host did not maliciously harm the U.S. beef industry in a 1996 program on mad cow disease. Plaintiffs who say the show caused a cattle market plunge that caused them to lose $11 million said they planned to appeal,...